K60P100M100SF2RM Datasheet, PDF (1177/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

Chapter 44 10/100-Mbps Ethernet MAC (ENET)
Pause frames are indicated by the length/type set to 0x8808. The two first bytes of a
pause frame following the type, defines a 16-bit opcode field set to 0x0001 always. A 16-
bit pause quanta is defined in the frame payload bytes 2 (P1) and 3 (P2) as defined in the
following table. The P1 pause quanta byte is the most significant.
Table 44-56. Pause Frame Format (Values in Hex)
12
55 55
15 16
00 00
69 70
26 6B
3
4
5
6
7
8
55
55
55
55
55
D5
Preamble SFD
17
18
19
20
21
22
00
00
00
00
88
08
Source Address
Type
71
72
AE
0A
CRC-32
9
10
11
12
13
14
01
80
C2
00
00
01
Multicast Destination Address
23
24
25
26
27 –68
00
01
hi
lo
00
Opcode
P1
P2
pad (42)
There is no payload length field found within a pause frame and a pause frame is always
padded with 42 bytes (0x00).
If a pause frame with a pause value greater zero (XOFF condition) is received, the MAC
stops transmitting data as soon the current frame transfer is completed. The MAC stops
transmitting data for the value defined in pause quanta. One pause quanta fraction refers
to 512 bit times.
If a pause frame with a pause value of zero (XON condition) is received, the transmitter
is allowed to send data immediately (see Full Duplex Flow Control Operation for details).
44.4.1.2 Magic Packets
A magic packet is a unicast, multicast, or broadcast packet, which carries a defined
sequence in the payload section.
Magic packets are received and inspected only under specific conditions as described in
Magic Packet Detection.
The defined sequence to decode a magic packet is formed with a synchronization stream
(six consecutive 0xFF bytes) followed by sequence of six consecutive unicast MAC
addresses of the node to be awakened.
The sequence can be located anywhere in the magic packet payload and the magic packet
is formed with standard Ethernet header and optional padding and CRC.
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.
1177